Update Travis Node version to 4.4
Update Travis Node version to 4.4

ScottLogic/BitFlux,jleft/d3fc-showcase,jleft/BitFlux,djmiley/d3fc-showcase,ScottLogic/d3fc-showcase,jleft/BitFlux,ScottLogic/d3fc-showcase,djmiley/d3fc-showcase,rjmcneill/d3fc-showcase,rjmcneill/d3fc-showcase,ScottLogic/d3fc-showcase,jleft/d3fc-showcase,jleft/d3fc-showcase,ScottLogic/BitFlux,rjmcneill/d3fc-showcase,djmiley/d3fc-showcase